A light-sensitive material comprises a support and a light-sensitive layer provided thereon containing silver halide, a reducing agent and a polymerizable compound. The light-sensitive material is used for a method in which a polymerizable compound is polymerized by a reducing agent to form a polymer image.
An embodiment of the image forming method using a wet development process is disclosed in U.S. Pat. No. 3,387,667 (corresponding to Japanese Patent Publication No. 45(1970)-11149) and U.S. Pat. No. 3,687,667 (Japanese Patent Publication No. 47(1972)-20741).
An improved embodiment using a dry development process is proposed in U.S. Pat. No. 4,629,676 (European Patent Publication No. 0174634A2 and Japanese Patent Provisional Publications No. 61(1986)-69062 and No. 61(1986)-73145). This embodiment comprises the steps of: imagewise exposing to light a light-sensitive material comprising a support and a light-sensitive layer provided thereon which contains silver halide, a reducing agent, a polymerizable compound; and heating the light-sensitive material. A latent image of the silver halide is formed by the exposure and the polymerizable compound is polymerized by heating within the area where the latent image has been formed.
Another embodiment is also disclosed in Japanese Patent Provisional Publications No. 61(1986)-260241, No. 2(1990)-141756, No. 2(1990)-141757, No. 2(1990)-207254 and No. 2(1990)-262662. The contents of the former two publications are described in European Patent Provisional Publication No. 0202490A. In this embodiment, a polymerization inhibitor is formed from an oxidation product of a reducing agent within the area where the latent image of the silver halide has been formed. The light-sensitive material used for this embodiment further contains a thermal polymerization initiator or a photopolymerization initiator. The polymerizable compound is polymerized by the thermal polymerization initiator or the photopolymerization initiator within the area where the latent image of the silver halide has not been formed.
A preferable embodiment of the above-described light-sensitive material and the image forming method using the material are proposed in Japanese Patent Provisional Publications No. 61(1986)-27542 and No. 61(1986)-278849. In the light-sensitive material, at least the polymerizable compound and the color image forming substance of the components are contained together with in the same microcapsules. The light-sensitive material having microcapsules containing the components gives an image of high quality.
An improvement of the light-sensitive material used in the above-mentioned image forming method has recently been proposed. U.S. Pat. No. 4,983,489 and Japanese Patent Provisional Publications No. 62(1987)-264041 and No. 2(1990)-262661 disclose a light-sensitive material containing a development inhibitor releasing (DIR) compound. An example of the DIR compound is an acid precursor which reacts with a base or neutralizes a base to reduce the base concentration in the light-sensitive layer and to terminate the excess development reaction. Another example is a compound which interacts with silver and a silver halide to inhibit the excess development reaction after a proper development is achieved. The light-sensitive material containing the DIR compound is improved in the stability of the image quality against the variation of the development conditions, such as the temperature and the development time.
The concept of the DIR (development inhibitor releasing) compound itself has been well known in the conventional photography. A DIR coupler or a DIR compound has frequently been used in a conventional silver halide photographic material.